1. Field of the Invention
The present invention relates to building curtain walls and, more particularly, but not by way of limitation, to methods of and apparatus for horizontal mullion bridging and sealing for collecting and diverting fluids, such as water infiltrating into the curtain wall system outwardly therefrom.
2. Description of Related Art
The above summary statement as to the field of the present invention is not intended to represent each embodiment or every aspect of the present invention. The advantages of building curtain wall technology are well known and accepted in the industry. Curtain walls are typically constructed of extruded aluminum frame support having generally U-shaped channels (although other shapes may apply) for supporting a plurality of panel members that serve as the exterior of a building. Such panel members are most often panes of glass, and often double pane glass sections, but other paneled building materials such as aluminum, granite, slate, or concrete are also utilized. Such panel members are often of identical size and shape. However, near doors, opening windows, or other access points into the building, panel members of different sizes and shapes may be utilized.
Curtain walls generally include a plurality of extruded horizontal members intersecting with vertical members. These vertical and horizontal extruded members will be referred to herein as mullions. The horizontal mullions are typically formed with structural body regions and tongue portions extending outwardly therefrom to facilitate the mounting of the panels. For this reason, an open intersection space is generally formed between the tongue portions of the horizontal mullions at the point where the vertical mullions intersect them. It typically is necessary to fill this tongue intersection space with a combination of material and sealant in order to control the collection and flow of moisture emanating from condensation, precipitation, etc. Typical remedies for removing the fluids that collect along horizontal mullions involve apparatus and systems for bridging and channeling the flow of fluid to exit portions of the curtain wall system. Such systems and apparatus often typically require intense manual labor at the job site to adequately provide the necessary seals, subassemblies and alignment of sealant and/or parts therefor relative to assembly of the curtain wall sections. One such relative part or subassembly involves a member referred to as a thermal isolator. The thermal isolator is an elongate, elastomeric member that is typically mounted along the frontal surface of a horizontal mullion. This horizontal surface typically includes a flanged region of the mullion that provides spacing for glass panels, or the like, as well as a means for mounting the thermal isolator therealong. This aspect will be discussed in more detail below.
Referring specifically now to the mullion intersection space, one example of a construction approach sometimes used in the industry and referenced above, is the manual application of sealant around vertical mullions at the intersection of horizontal mullions. The sealant must be manually ramped at an incline to force the collecting fluid out of the intersection and toward the exit portion along the horizontal mullion. With this technique, the quality of the ramping of the sealant is obviously dependent on the skill and care of the laborer. The operation also adds additional cost and time to the project. Furthermore, human error and inconsistency is introduced when vast quantities of labor are required to apply sealant in the curtain wall system. Two patent applications that address these and related water diversion issues are U.S. patent application Ser. No. 10/836,081, filed Apr. 29, 2004, and U.S. patent application Ser. No. 10/833,990, filed Apr. 27, 2004, both assigned to the assignee of the present invention and incorporated herein by reference.
Yet another approach to the problem described above is the use of a preformed barrier plug adapted for positioning at the intersection of the horizontal and vertical mullions. A typical barrier plug may fill the space normally occupied by both the horizontal mullion tongue and the thermal isolator secured therealong. In such configurations, the thermal isolator is generally cut where it engages the barrier plug. The thickness of the barrier plug is that necessary to accommodate the spacing of the flange and the thermal isolator for flush receipt of a pressure plate outwardly thereof. The uniformity and consistency of the mounting of a pressure plate against a thermal isolator is important, and problems can occur when the thermal isolator must be cut and applied in sections. The present invention addresses these problems by providing a method and apparatus permitting a continuous length of thermal isolator material to be secured along the horizontal mullion of a curtain wall and uniformly across the junction of a vertical mullion in association therewith.